1. Field of the Invention
This invention relates to a photo-taking lens having an image deflecting device suitable for a photographic camera or a video camera, and in particular to a simple photo-taking lens of good operability which prevents the entire optical system from becoming bulky.
2. Related Background Art
When a photograph is taken from on a vehicle or an aircraft which is in progression, vibration is transmitted to the photo-taking system and the photographed image becomes blurred. As means for preventing this, for example, U.S. Pat. No. 3,212,420 has heretofore proposed an image stabilizing optical system as shown in FIG. 1 of the accompanying drawings wherein an optical member 11 having a variable vertical angle prism action is disposed forwardly of a phototaking system 10 so that the vertical angle of the optical member 11 is varied in conformity with the magnitude of the tilting of the photo-taking system, whereby the picture plane is deflected and a still image is obtained on the imaging plane.
However, the method of disposing a variable vertical angle prism as image stabilizing means forwardly of the photo-taking system has required the disposition of a variable vertical angle prism of a size corresponding to the size of the effective diameter of the forward lens group of the photo-taking system which is generally large, and this has led to bulkiness and reduced operability of the entire optical system. Such disadvantages will appear particularly remarkably if such image stabilizing means is provided in a telephoto lens in which the effective diameter of the forward lens group is large. There is U.S. Pat. No. 3,942,862 as other related art.